Toothbrush



Jan. 3, 1967 IMU) WWII

United States Patent O M 3,295,156 TOOTHBRUSH Joseph H. Brant, Summit, NJ., assignor to Colgate- Palmolive Company, New York, NX., a corporation of Delaware Filed Apr. 14, 1965, Ser. No. 448,048 4 Claims. (Cl. 15-167) This invention relates to a toothbrush. More particularly, this invention relates to a novel toothbrush having an unique tooth cleaning head.

Broadly, this invention contemplates a toothbrush comprising a base member having a handle portion at one end thereof and a head portion at the opposite end, and a plurality of synthetic fiber bristles connected at one end to said head portion, their free ends being upstanding, at least some of said free ends being split longitudinally for a portion of the bristle length, and at least some of said free ends being intact, said bristles with intact free ends being shorter than said bristles with split ends.

In the drawing:

FIG. l is a partially broken away, enlarged, fragmentary, side elevational view of a head portion of a toothbrush of this invention;

FIG. 2 is a cross-sectional view along the line 2 2 of FIG. 1;

FIG. 3 is a perspective view of another embodiment of my invention;

FIG. 4 is an enlarged, fragmentary cross-sectional view along the line 4 4 of FIGURE 3; and

FIG. 5 is an enlarged side-elevational view of the bristles of FIGS. l through 4.

As seen in FIGURE 3, the toothbrush comprises a handle 2 portion and a head 6 portion. A tooth cleaning portion 8 is composed of bristles 10 which are connected to the head 6 in an upstanding manner.

The bristles 10, which together form the tooth cleaning portion 8, are composed of agged bristles 12, that is, bristles whose free ends have been longitudinally split, for a portion of the bristle length, into at least two parts, as well as bristles 14 whose free ends are intact.

The intact bristles 14 are shorter than the flagged bristles 12 so that when cleaning the teeth with this toothbrush and exerting pressure on the teeth by the toothbrush the flexible ags 18 will bend until the teeth are contacted by the more rigid intact bristles 14 which restrain further bending of the flags 18.

`In this manner, cleaning tot the teeth is greatly facilitated by a wiping faction exerted on the teeth by the sides, rather than the points, of the flags 18 as well as by contact of the teeth by the points of the relatively rigid intact bristles 14.

In order to control the degree of bending of the longitudinally split bristles, the height of the short intact bristles 14 should not exceed 95 of the height of the longitudinally split bristles 12 which may be from about 0.25 to about 0.75 inch tall.

For optimum side contact wiping action on the teeth by the ilags 18, it is preferred that the intact bristles 14 be about 70% to about 95% as tall as the longitudinally split bristles 12.

As seen in FIGURES 1 and 2, the intact 14 and longitudinally split bristles 12 may be arranged on the toothbrush in a random manner to achieve the enhanced beneiicial cleaning action of this toothbrush.

FIGURE 4 illustrates an alternative bristle arrangement wherein the short intact bristles 14 are arranged in tufts 24 which border, on at least one side, the tufts 28 of the flagged bristles 12.

Moreover, the bristles may be arranged so that each longitudinally split bristle borders on at least one shorter having intact free ends (not shown).

Patented Jan. 3, i967 ICC Up to about 90% and preferably from about 20% to about of the toothbrush bristles 10 have -their free ends longitudinally split into at least two parts which constitute the flags. The intact bristles 14 comprise at least 10% of the toothbrush bristles 10.

Although the number of flags 18 on each split bristle 12 may vary widely, even exceeding 20 ilags per split bristle, it is preferred that these be from about tive to about thirteen flags per split bristle 12 because it has been found that more eicient cleaning of the teeth is thus obtained and such a toothbrush has a longer life than if the split bristles 12 include a greater number of I flags 18.

It should be understood, however, that the number of ilags 18 per longitudinally split bristle 12 may Vary even on the same toothbrush.

The length of the longitudinal split may also vary widely. Generally, the bristles should be split up to one half the bristle length. However, it is preferred that the bristles be split for 30% of the bristle length.

Generally, the diameter of the base 32 of the split bristles 12 as well as the diameter of the intact bristles 14 will vary from about 0.008 inch to about 0.02 inch and preferably from about 0.010 to about 0.016.

The bristles used in this toothbrush may be manufactured from any synthetic fiber which can be flagged (longitudinally split). Among such iibers are polyamides, polyesters, polyacrylates and the like, such as polyhexarnethyl sebacate or adipamide, polycaprolactarn, polyethylene terephthalate, polystyrene or polypropylene, and the like.

Additionally, other toothbrush bristles may be used Which are manufactured from a copolymer of polyvinylchloride or polyvinylidene chloride with polystyrene.

Mixtures of synthetic resins may also be used. Among the materials which may be admixed are polystyrene, styreneacrylonitrile copolymers, and linear ber-forming polyamides, such as polyhexarnethylene adipamide.

Flagging of the bristles may be accomplished in any suitable manner, such as by cold drawing them to the breaking point or by subjecting them to an impact on their surface, as for example by thrusting them into the rotating blades of a fan-like agging machine without attempting to penetrate the individual filaments.

If desired, the bristles may be agged before attaching them to the head portion of the base member. Alternatively, the bristles may be attached to the head portion of the base member and then flagged as described. However, if the bristles are to be flagged after assembly on the head portion of the base member, care must be taken not to insert the free end portion of the bristles too far into the machine because the shorter bristles will theny come into contact With the machine and will also be agged.

The bristles 10 may be attached to the head 6 portion of the toothbrush in any suitable manner, such as by cementing the bristles 10 into pockets which have been drilled into the head 8 portion.

The bristles may suitably be arranged in three or four rows of bristles or tufts of bristles, depending rupon whether the brush is to be used by a child (three rows) or by an adult (four rows). Generally, ehowever, a satisfactory toothbrush for an adult will comprise tufts -having from about fifteen to about iifty bristles per tuft.

The head and handle portions, which together comprise the base member, may be made from any rigid polymeric material, such as polystyrene, cellulose acetate or polyethylene and the like. However, such materials are well known in the art and the invention is not to be construed as limited to any one particular material.

The toothbrush of this invention is particularly advantageous. The agged portions of the bristles clean the teeth using the side contact points, thereby facilitating a wiping action which it has been found is extremely desirable. The intact bristles themselves are relatively rigid and clean through contacting the teeth by the points of the intact bristles. Additionally, the intact bristles determine the degree to which the agged portion of the bristles will bend and thus the length of the side contact points, thereby providing for a toothbrush with the desired degree of rigidity and optimum cleaning action.

Additionally, because of the multiple flagging, the tooth brush is better able to support powdered dentifrices than a standard toothbrush because applicants flagged toothbrush provides a more continuous surface than does a standard toothbrush.

Furthermore, because of the multiple agging of the toothbrush bristles, when a foaming dentifrice is used,"l

more foam will be produced because of greater aeration due to the flags on the bristles. Moreover, the life of the toothbrush is extended, despite the relatively small diameter of the flags, because these ags have the desired degree of flexibility and do not permanently deform when repeatedly bent as compared to toothbrushes whose bristles are of a greater diameter.

While this invention has been described in terms of certain embodiments, the invention is not to be construed as limited except as set forth by the following claims.

What is claimed is:

1. A toothbrush comprising a base member having a handle portion at one end thereof and a head portion at the opposite end, and a plurality of synthetic ber bristles connected at one end to said head portion, their free ends being upstanding, from 20% to about 80% of said free ends being longitudinally split or llagged into from about two to about twenty parts for up to one half of the bristle length, the remainder of said free ends being intact, said bristles with intact free ends being from about to 95% as tall as said longitudinally split bristles and cooperating with the flagged bristles to control the degree of bending thereof, whereby the cleaning of the teeth is facilitated by a wiping action exerted on the teeth by the sides of the longitudina-lly split bristles as well as by contact with the tips of the longitudinally split and intact. bristles.

2. A toothbrush in accordance with claim 1 wherein. said agged bristles are split into from about ve to aboutthirteen parts.

3. A toothbrush in accordance with claim 1 wherein the agged bristles are split for up to 30% of the bristle length.

4. A toothbrush in accordance with claim 1 wherein said longitudinally split bristles are bordered by said intact bristles on at least one side thereof.

References Cited by the Examiner UNITED STATES PATENTS 1,128,139 2/1915 Hoffman 15--117' 1,382,681 6/1921 Segal 15-167 1,482,027 1/1924 Ochse 15-167 X 1,664,797 4/1928 Stone 15-167 X 3,103,679 9/1963 Clemens 15-167 FOREIGN PATENTS 811,072 4/ 1959 Great Britain.

897,404 5/ 1962 Great Britain.

955,778 4/ 1964 Great Britain.

CHARLES A. WILLMUTH, Primary Examiner.

P. FELDMAN, Assistant Examiner. 

1. A TOOTHBRUSH COMPRISING A BASE MEMBER HAVING A HANDLE PORTION AT ONE END THEREOF AND A HEAD PORTION AT THE OPPOSITE END, AND A PLURALITY OF SYNTHETIC FIBER BRISTLES CONNECTED AT ONE END TO SAID HEAD PORTION, THEIR FREE ENDS BEING UPSTANDING, FROM 20% TO ABOUT 80% OF SAID FREE ENDS BEING LONGITUDINALLY SPLIT OR FLAGGED INTO FROM ABOUT TWO TO ABOUT TWENTY PARTS FOR UP TO ONE HALF OF THE BRISTLE LENGTH, THE REMAINDER OF SAID FREE ENDS BEING INTACT, SAID BRISTLES WITH INTACT FREE ENDS BEING FROM ABOUT 70 TO 95% AS TALL AS SAID LONGITUDINALLY SPLIT BRISTLES AND COOPERATING WITH THE FLAGGED BRISTLES TO CONTROL THE DEGREE OF BENDING THEREOF, WHEREBY THE CLEANING OF THE TEETH IS FACILITATED BY A WIPING ACTION EXERTED ON THE TEETH BY THE SIDES OF THE LONGITUDINALLY SPLIT BRISTLES AS WELL AS BY CONTACT WITH THE TIPS OF THE LONGITUDINALLY SPLIT AND INTACT BRISTLES. 